1. Field of the Invention
The invention relates generally to integrated computer modules and, more specifically, to an integrated computer module having a data integrity latch that is enabled during disk drive read/write operations.
2. Description of the Related Art
Today's personal computers (PC's) are usually sold in a desktop configuration or a notebook configuration. Desktop PC's are generally housed in a relatively large chassis containing a main printed circuit board or "motherboard" and other components that are incorporated into or connected to the motherboard. The components may be located inside or outside of the chassis. Typical internal components include a power supply, a central processing unit (CPU), random access memory (RAM), a mass storage device such as a magnetic disk drive, expansion cards connected to a bus on the motherboard, and various peripherals mounted on "rails" in "bays" within the chassis and electrically connected to the motherboard or an associated expansion card by a ribbon cable or the like. Typical expansion cards are a SCSI adapter, a sound adapter, and a network adapter. Typical bay-mounted peripherals are a magnetic disk drive, a floppy drive, a tape drive or a CD-ROM drive. Typical external "peripherals" include user input devices such as a keyboard, a mouse, a microphone, a joystick, a graphics tablet or a scanner and user output devices such as speakers a printer, and a video display device (e.g. a CRT display or an LCD display). The video adapter that controls the display, as with other adapters, may be integrated into the motherboard or provided on a separate expansion card.
The users of desktop PC's may be divided into two divergent groups: (1) experienced users who understand the individual components and tend to frequently upgrade their PC's by replacing such components, and (2) new users who do not understand or even want to understand the individual components. The latter group may prefer to replace the entire PC, if they upgrade at all. With respect to both groups, however, it has been observed that the need or desire to upgrade occurs far sooner with respect to some components than with respect to other components. In particular, users more frequently upgrade the CPU, the RAM, the magnetic disk drive, and the video adapter. These upgrades tend to provide more capacity and more speed because of rapid technological advancements on the part of manufacturers in response to ever-increasing demands from ever more complicated and more graphics intensive software applications and an associated increase in file sizes. Both user-types less frequently need or desire to upgrade the monitor, the speakers, the keyboard or the power supply, however, because these latter components have withstood the test of time and employ technologies that are less prone to obsolescence.
These inventors expect that the computer paradigm will move from a large chassis full of individual components of different manufacture toward a readily upgraded system consisting of two primary components: (1) an integrated computer module that compactly houses the frequently upgraded components (e.g. the CPU, the memory, the disk drive, and the video adapter) and provides a module connector for interfacing the module's electronics with peripherals, and (2) a "host assembly" with a docking bay that receives the module and provides a host connector that mates with the module connector. The host assembly can comprise any "shell" that includes the bay that receives the integrated computer module. The docking bay may be in a host assembly that doubles as a peripheral or in an intermediate assembly that is connected to conventional peripherals. The host assembly, for example, may function and appear generally like a conventional CRT display, save for the addition of the docking bay. A CRT-like host assembly of this nature would also provide a first connector for receiving input from a keyboard and, in all likelihood, a second connector for receiving input from a mouse. As another example, the host assembly may appear like a conventional tower chassis that contains a docking bay for receiving the module, and suitable electronics (e.g. a printed circuit board or PCB, cables, and so on) to interface the integrated computer module to conventional expansion cards via an expansion bus, and to conventional peripherals like a display, a keyboard, and a mouse, via connector ports built-in to the host assembly or carried by an expansion card.
There are a number of challenges associated with packing computer components and storage capability into a small integrated computer module. One such challenge is maintaining safe operating temperatures given a microprocessor and other components that dissipate relatively high levels of power. Another challenge for designing and building such modules is providing adequate shock protection for sensitive structures like disk drives. Still another challenge is providing an arrangement of components which allows for cost effective manufacturing processes. Yet another challenge is making sure the module is not abruptly removed from the host assembly during data-critical operations.
Computer modules and associated bays have already been proposed. For example, in U.S. Pat. No. 5,463,742 that issued in 1995 to Kobayashi, assigned to Hitachi, the inventor discloses a "personal processor module" (PPM) that fits within a notebook type docking station or a desktop type docking station, or simply attaches to a docking housing 6 that is cabled to a keyboard and a monitor. (See FIG. 1). As shown in FIG. 6, the '742 Patent discloses a PPM with an opening 100 so that the PPM cannot be hurriedly removed from the docking station. As shown in FIGS. 21 and 22, however, the PPM does not hold itself in the docking station, but rather passively submits to being held by two external arms 134, 136 that grasp the sides of the PPM, pull it into the docking station and hold it there. In the absence of power in the host assembly for releasing the PPM, therefore, it may be somewhat difficult to removed the PPM.
In U.S. Pat. No. 5,640,302 that issued in 1997 to Dan Kikinis, assigned to Elonex IP Holdings, the inventor discloses a modular portable computer which has modules that are externally held in a similarly passive manner. In FIGS. 25 and 26, for example, it can be seen that locking extensions 1040, 1042 are provided on moveable cooling elements 1036, 1038 located above and below the module 1013 in a sandwich-like arrangement. Again, it may be somewhat difficult to removed the module in the absence of power in the host assembly.
There remains a need, therefore, for an integrated computer module having a data integrity latch that is enabled during data-critical operations (e.g. disk drive read/write operations) and may be overridden in the absence of power.